<template>
  <div class="cropper-wrapper">
    <!-- element 上传图片按钮 -->
    <template v-if="!isPreview">
      <el-upload
        class="upload-demo"
        action=""
        drag
        :auto-upload="false"
        :show-file-list="false"
        :on-change="handleChangeUpload"
      >
        <div class="upload-dragger">
          <i class="el-icon-upload"></i>
          <div class="el-upload__text">点击上传</div>
          <div class="el-upload__tip">
            （注：照片尺寸裁剪为800px*800px）
          </div>
        </div>
      </el-upload>
    </template>
    <div class="pre-box" v-else>
      <img :src="previewImg" alt="裁剪图片" style="width: 150px" />
      <el-upload
        class="upload-demo"
        action=""
        :auto-upload="false"
        :show-file-list="false"
        :on-change="handleChangeUpload"
      >
        <el-button type="primary" plain>更换图片</el-button>
      </el-upload>
    </div>
    <!-- vueCropper 剪裁图片实现-->
    <el-dialog
      title="图片剪裁"
      :visible.sync="dialogVisible"
      class="crop-dialog"
      append-to-body
    >
      <div class="cropper-content">
        <div class="cropper" style="text-align: center">
          <vueCropper
            ref="cropper"
            :img="option.img"
            :outputSize="option.size"
            :outputType="option.outputType"
            :info="true"
            :full="option.full"
            accept=".jpg,.jpeg,.png"
            :canMove="option.canMove"
            :canMoveBox="option.canMoveBox"
            :original="option.original"
            :autoCrop="option.autoCrop"
            :fixed="option.fixed"
            :fixedNumber="option.fixedNumber"
            :centerBox="option.centerBox"
            :infoTrue="option.infoTrue"
            :fixedBox="option.fixedBox"
            :autoCropWidth="option.autoCropWidth"
            :autoCropHeight="option.autoCropHeight"
            @cropMoving="cropMoving"
          />
        </div>
      </div>
      <div class="action-box">
        <el-upload
          class="upload-demo"
          action=""
          :auto-upload="false"
          :show-file-list="false"
          :on-change="handleChangeUpload"
        >
          <el-button type="primary" plain>更换图片</el-button>
        </el-upload>
        <el-button type="primary" plain @click="clearImgHandle"
          >清除图片</el-button
        >
        <el-button type="primary" plain @click="rotateLeftHandle"
          >左旋转</el-button
        >
        <el-button type="primary" plain @click="rotateRightHandle"
          >右旋转</el-button
        >
        <el-button type="primary" plain @click="changeScaleHandle(1)"
          >放大</el-button
        >
        <el-button type="primary" plain @click="changeScaleHandle(-1)"
          >缩小</el-button
        >
        <!-- <el-button type="primary" plain @click="downloadHandle('blob')"
          >下载</el-button
        > -->
      </div>
      <div slot="footer" class="dialog-footer">
        <el-button @click="dialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="finish" :loading="loading"
          >确认</el-button
        >
      </div>
    </el-dialog>
  </div>
</template>

<script>
import { VueCropper } from "vue-cropper";
import * as List from "@/api/List";

export default {
  components: { VueCropper, List },
  name: "Cropper",
  data() {
    return {
      isPreview: false,
      dialogVisible: false,
      previewImg: "", // 预览图片地址
      // 裁剪组件的基础配置option
      option: {
        img: "", // 裁剪图片的地址
        info: false, // 裁剪框的大小信息
        outputSize: 1, // 裁剪生成图片的质量
        outputType: "png", // 裁剪生成图片的格式
        canScale: true, // 图片是否允许滚轮缩放
        autoCrop: true, // 是否默认生成截图框
        canMoveBox: true, // 截图框能否拖动
        autoCropWidth: 350, // 默认生成截图框宽度
        autoCropHeight: 350, // 默认生成截图框高度
        fixedBox: true, // 固定截图框大小 不允许改变
        fixed: false, // 是否开启截图框宽高固定比例
        fixedNumber: [1, 1], // 截图框的宽高比例
        full: false, // 是否输出原图比例的截图
        original: false, // 上传图片按照原始比例渲染
        centerBox: false, // 截图框是否被限制在图片里面
        infoTrue: true // true 为展示真实输出图片宽高 false 展示看到的截图框宽高
      },
      // 防止重复提交
      loading: false,
      file: "",
      dataurl: ""
    };
  },
  methods: {
    // 上传按钮 限制图片大小和类型
    handleChangeUpload(file, fileList) {
      this.file = file.raw.name;
      const isJPG =
        file.raw.type === "image/jpeg" || file.raw.type === "image/png";
      const isLt2M = file.size / 1024 / 1024 < 2;
      if (!isJPG) {
        this.$message.error("上传图片只能是 JPG/PNG 格式!");
        return false;
      }
      if (!isLt2M) {
        this.$message.error("上传图片大小不能超过 2MB!");
        return false;
      }
      // 上传成功后将图片地址赋值给裁剪框显示图片
      this.$nextTick(async () => {
        // base64方式
        // this.option.img = await fileByBase64(file.raw)
        this.option.img = URL.createObjectURL(file.raw);
        this.loading = false;
        this.dialogVisible = true;
      });
    },
    // 放大/缩小
    changeScaleHandle(num) {
      num = num || 1;
      this.$refs.cropper.changeScale(num);
    },
    // 左旋转
    rotateLeftHandle() {
      this.$refs.cropper.rotateLeft();
    },
    // 右旋转
    rotateRightHandle() {
      this.$refs.cropper.rotateRight();
    },
    // 下载
    // downloadHandle(type) {
    //   let aLink = document.createElement("a");
    //   aLink.download = "author-img";
    //   if (type === "blob") {
    //     this.$refs.cropper.getCropBlob(data => {
    //       aLink.href = URL.createObjectURL(data);
    //       aLink.click();
    //     });
    //   } else {
    //     this.$refs.cropper.getCropData(data => {
    //       aLink.href = data;
    //       aLink.click();
    //     });
    //   }
    // },
    // 清理图片
    clearImgHandle() {
      this.option.img = "";
    },
    // 截图框移动回调函数
    cropMoving(data) {
      // 截图框的左上角 x，y和右下角坐标x，y
      // let cropAxis = [data.axis.x1, data.axis.y1, data.axis.x2, data.axis.y2]
      // console.log(cropAxis)
    },
    finish() {
      // 获取截图的 blob 数据
      this.$refs.cropper.getCropBlob(blob => {
        this.loading = true;
        this.dialogVisible = false;
        this.previewImg = URL.createObjectURL(blob);
        this.isPreview = true;
      });

      // 获取截图的 base64 数据
      this.$refs.cropper.getCropData(data => {
        console.log(data);
        //调用
        var file = this.dataURLtoFile(data, this.file);
        console.log(file);
        const formData = new FormData();
        formData.append("file", file);
        console.log(formData);
        List.fileUpload(formData).then(response => {
          if (response.code === 200) {
            this.msgSuccess("上传成功");
            console.log(response.result);
            let url = response.result;
            let urlStr = url.lastIndexOf("/");
            let fileName = url.substr(urlStr + 1);
            console.log(fileName);
            // this.$emit("listenToChildEvent",1113)
          }
        });
      });
    },
    //将base64转换为文件
    dataURLtoFile(dataurl, filename) {
      var arr = dataurl.split(","),
        mime = arr[0].match(/:(.*?);/)[1],
        bstr = atob(arr[1]),
        n = bstr.length,
        u8arr = new Uint8Array(n);
      while (n--) {
        u8arr[n] = bstr.charCodeAt(n);
      }
      return new File([u8arr], filename, { type: mime });
    }
  }
};
</script>

<style lang="scss" scoped>
/deep/.upload-dragger {
  background-color: #fff;
  border: 1px dashed #d9d9d9;
  border-radius: 6px;
  box-sizing: border-box;
  width: 100%;
  height: 100%;
  text-align: center;
  cursor: pointer;
  position: relative;
  overflow: hidden;
}

.cropper-wrapper {
  //height: calc(100vh - 50px);
  .pre-box {
    button {
      width: 100px;
      margin-top: 15px;
    }
  }
}

.crop-dialog {
  .cropper-content {
    padding: 0 40px;

    .cropper {
      width: auto;
      height: 350px;
    }
  }

  .action-box {
    padding: 25px 40px 0 40px;
    display: flex;
    justify-content: center;

    button {
      width: 80px;
      margin-right: 15px;
    }
  }

  .dialog-footer {
    button {
      width: 100px;
    }
  }
}
</style>
